Conventionally, to reduce vibrations transmitted from the engine to the vehicle body side, there is a technology in which an engine is elastically supported through members called a torque rod which includes insulators and a rod part relative to the vehicle body side. Further, an active vibration reduction device for actively reducing vibrations from the engine to the body side by cancelling the vibrations of the engine by an antiphase vibrations of an inertial mass to increase the vibration reduction effect with the torque rod by providing an actuator for generating at an inertial mass vibrations which is antiphase with the vibrations of the engine (for example, see FIG. 2 in Patent Document 1).
More specifically, the active vibration reduction device of Patent Document 1 includes an engine-side insulator to be mounted on the side of the engine and the torque rod having a rod part for connecting these a pair of the insulators, an inertial mass supported by the rod part, an actuator for reciprocatingly drive the inertial mass in an axial direction of the rod part, and a control means for controlling the reciprocating drive of the inertia mass in the axial direction of the rod part.
Provided inside a body side cylindrical hollow member forming a frame of the vehicle body side insulator are body-side shaft members having a circular column in a coaxial circles. The body side shaft member is mounted on the vehicle body side. In a vehicle body space having a ring shape sectioned by an inner circumferential wall of the vehicle body side cylindrical hollow member and an outer circumferential wall of the vehicle body side shaft member is filled at a high density with an elastic member such as rubber. This provides an elastic support through an elastic member between the vehicle body side shaft member and the vehicle body side cylindrical hollow member.
On the other hand, provided inside the engine side cylindrical hollow member forming the frame of the engine side insulator are engine side shaft members in a cylindrical column shape coaxially. The engine side shaft members are mounted on the engine side. Provide inside the engine side space in a ring shape defined by the inner circumferential wall of the engine side cylindrical hollow member and an outer circumferential wall of the engine side shaft member are engine side elastic members which partially extends in a direction orthogonal with the shaft direction of the rod part.
Further, there is no elastic member at a part along the shaft direction of the rod part out of the ring-shape engine side space. Instead of this, a pair of stoppers including elastic members such as rubber, etc. are installed at an inner circumferential wall part of the hollow cylindrical member extending along an axial direction of the rod part out of the ring-shape engine side space. A pair of the stoppers restrict a movable range of the engine side shaft member extending along an axial direction of the rod part, i.e., a displacement of the power plant including the engine and the transmission. This prevents interference between the engine, the vehicle body, or accessories and provides a role of increasing a durability performance of the engine.
This configuration provides an elastic support between the engine side shaft member and the engine side hollow cylindrical member through the engine side elastic member installed so as to partially extend in a direction orthogonal with an axial direction of the rod part.
The active vibration reduction device of Patent Document 1 can reduce the vibrations transmitted from the engine to the vehicle body side.